Search

Multispectral remote sensing is a new effective technique to evaluate crops phenology, plant health and the weeds presence. The study aims to exploit the possibilities of multispectral imaging for detection the weeds in winter wheat. The phenological changes of different weeds was also investigated, employing the calculation of six vegetation indexes during a period of three months. The vegetation indexes were as follows: CIG, GRNDVI, GRVI, CVI, NDWI2, NDVI. The influence of weed species on the value of the corresponding vegetation index within each reporting period was investigated. The control value was the one calculated for areas sown with wheat without weeds. It is established that the factors: phenophase and weed type have a statistically significant influence on the researched indexes. The GRVI is the only index on which plant phenophase does not have a significant effect. Regarding the NDVI values, no permanent trend for the presence/absence of a certain weed was found. In almost all phenophases, high values of the index were calculated in both weed varieties and weed free wheat. [ABSTRACT FROM AUTHOR]

In the present work, the "genotype-environment" interaction of the yields of essential oil and oilseed technical crops in Bulgaria is investigated and analyzed. Data are presented for a fourteen-year period related to yields of: rose, lavender, mint, coriander, valerian and lemon balm, sunflower, canola, soybeans, peanuts, pumpkins. It was established that among the essential oil crops with the highest yields is mint (9250 kg/ha), and with minimum yields - coriander (914.3 kg/ha). Mint proves to be the crop with the greatest degree of susceptibility to environmental factors in terms of yields compared to other crops of this group. Among the oilseed technical crops, rapeseed has the highest, but unstable, yields (2063.8 kg/ha). Pumpkins for seeds are the lowest (662.9 kg/ha). The most resistant to external factors are sunflowers and pumpkins, which makes them a preferred crop for cultivation in regions with changing climatic conditions. [ABSTRACT FROM AUTHOR]

A comparative technological study of wines from four seedless coloured hybrid vine forms-30/2, 30/3, 30/10, 31/9 and the varieties-Syrah clone 174, Sangiovese, Marselan and Regent. It was found that on the content of trans-resveratrol, quercetin and antioxidant activity of wine, all studied hybrid forms are superior to Sangiovese and inferior to Syrah-clone 174. With a high degree of balance and stability of environmental conditions of the varieties are Syrah-clone 174, Marselan and Regent, and of the hybrid forms-30/10 and 30/2. Various representatives of the volatile aromatic composition have been identified in the studied wines, belonging to the groups of higher alcohols, esters and terpenes, acetaldehyde and methanol. The total quantitative presence of volatile compounds is higher in the wines of the hybrid forms compared to those of the control varieties. The content of sugars and acids in grapes, and alcohol and sugars in wine in hybrid forms and varieties does not differ significantly. The amounts of extract, titratable acids, anthocyanins are higher in hybrid forms. The highest amount of total phenols is observed in the wine of 30/10-3295.66 mg/dm³, and the lowest in Sangiovese-2060.91 mg/dm3 . With the highest organoleptic evaluation is the wine from Syrah clone 174-86.0, and from the seedless coloured hybrid forms are 30/10-83.0 and 30/3-80.0. It is possible through staged sexual hybridization to create seedless coloured varieties suitable for the production of quality wines, characterized by high taste characteristics, nutritional and medicinal value. [ABSTRACT FROM AUTHOR]

A comparative biometric characterization of the organs in the female part of the flower was performed in a large group of seedless varieties of vines. It has been established that, depending on the degree of their biometric similarity at the base of the inflorescence, the studied seedless varieties of vines form six generalized clusters, three in the middle and five in the upper parts - at the top, the majority of which consist of sub-clusters, gathered at the respective Euclidean distance. The use of the two mathematical-statistical methods - hierarchical cluster analysis and single-factor analysis of variance allows the obtaining of statistically reliable information about the importance of the individual components of the vine flower in the grouping of the seedless varieties of vines. The established differences in the parameters of the organs from the female part of the flower confirm the non-simultaneous morphological and cytoembryological development of the flower buttons depending on the variety, as well as the enormous polymorphism in this group of varieties. [ABSTRACT FROM AUTHOR]

The objects of research are sixteen cultivars nectarines and elite, which data were reported for the period 2019-2021 on the territory of the Fruit Growing Institute - Plovdiv. The purpose of the study is to group and evaluate according to the degree of frost on their flowers. For this purpose, single factor analysis of variance and Tukey’s test were applied for difference estimation as well as hierarchical cluster analysis. It was established that during the three years of research, the Sunfree cultivar freezes 100%, which made it the most susceptible variety to temperature effects. The least consequences of negative temperatures on the flowers are the least in the Gergana variety for 2019 (33%), the Morciani 90 for 2020 (84%), and the El. 4-151 in 2021 (72.66%). As a result of the studies, it was established that the resistance to low temperatures in different cultivars and elites is largely determined by the degree of coincidence of the phenological stages: early bloom and full bloom with those negative temperatures. [ABSTRACT FROM AUTHOR]

A study of the amount of colouring substance in the skins and juice of grapes and raisins of seedless vine forms with coloured grape juice of six hybrid combinations was performed. It was found that most of the hybrid forms of all crosses were superior to the mother variety Alicante Bouschet in the amount of anthocyanins in the grape juice, and only a few ones have mathematically proven differences. Most of them do not differ from the parent variety in colour intensity and colour shade, as well as in the percentage of yellow, red and blue colour. The ‘Alicante Bouschet’ variety has a proven lower content of anthocyanins in the skins of grapes and raisins of several hybrid forms. There is a proven high or moderate positive correlation between the content of anthocyanins in the skins and the juice of the grapes and the intensity of the colour in the hybrid forms of most crosses. Approximately 47% of the increase in the intensity of the colour of the grape juice can be explained by an increase in the amount of anthocyanins, and only 27% of the reasons for the changes in the intensity of the colour of the grapes are due to factors that do not affect changes in the content of anthocyanins in them. [ABSTRACT FROM AUTHOR]

The degree of the phenotypic similarity and differences between 61 seedless vine varieties was studied by grouping them according to economically important phenological, agrobiological and technological indicators. A multidimensional statistical approach is applied - a cluster analysis, which provides possibilities of establishing relatively homogeneous groups (clusters), based on a set of certain indicators. As the cluster analysis does not perform any tests for the statistical significance of the results, it is combined with a factor analysis, which provides information on the reasons leading to the distribution of the individual varieties in different clusters and the merging of others into one cluster. The applied factor analysis transformed all the studied indicators into seven main components, explaining 76% of the total variance. The transformation of these traits to the corresponding number of factors and the indicators in them, which explain that the varieties belong to the separate clusters, was established. The limits of the phenotypic similarity and differences between the studied seedless vine varieties and the conditional parameters of the polymorphism with their economically significant ampelographic characteristics were determined. The presented grouping can be used for taxonomic purposes, as well as in the selection to create new seedless vine varieties. By applying targeted agro-technical measures, the desired change in the indicators of the first and second factors in the individual groups of traits can be actively influenced. [ABSTRACT FROM AUTHOR]

The aim of the present study was to determine the effect of two flaxseed oil levels in the diet of male Ross 308 broilers on the growth performance, feed consumption, slaughter analysis, meat quality, chemical and fatty acid composition of breast and thigh muscles. A total of 180 one-day-old broiler chicks were weighed individually, randomly distributed in 3 groups (n=60 birds in each group; 4 replicates × 15 birds per replicate) and fed to 42 days of age with following diets containing: first group (G1 ) – 0%; second group (G2 ) – 1.5% and third group (G3 ) – 3.0% flaxseed oil. At the end of the experiment, chickens attained average body weight of 2485 ± 49 g (G1 ), 2500 ± 49 g (G2 ) and 2551 ± 47 g (G3) without statistically significant differences – Р > 0.05. Feed conversion ratio (FCR) for all periods was 1.74 kg/kg (G1), 1.58 kg/ kg (G2) and 1.57 kg/kg (G3). Higher water-holding capacity (WHC) was found for breast fillet in G1 and G2 compared to G3 – P < 0.05, and for thigh muscle in G1 and G3 compared to G2 – P < 0.05. No differences between the groups were found with regard to the tenderness of the meat – Р > 0.05. With regard to fatty acids, with increasing the amount of flaxseed oil in the diet, the content of oleic, palmitic and palmitoleic acids in the breast fillet decreased while the quantity of linoleic and linolenic acids increased drastically – from 4.60 ± 0.81 (G1 ) to 5.80 ± 0.87 (G2 ) and to 13.27 ± 0.15 (G3 ), and from 0.07 ± 0.03 (G1 ) to 0.80 ± 0.23 (G2 ) and to 6.77 ± 0.55 (G3 ). The tendency of changes in fatty acids in thigh meat was similar – palmitic and palmitoleic acids decreased, and linoleic and linolenic acids increased dramatically – from 6.47 ± 0.03 (G1 ) to 10.20 ± 0.12 (G2 ) and to 11.23 ± 1.59 (G3 ), from 0.10 ± 0.06 (G1 ) to 2.60 ± 0.23 (G2 ) and to 5.67 ± 1.13 (G3 ). The addition of flaxseed oil in the diet decreased the amount of SFA, increased UFA, and PUFA in particular, which once again was due to the increased content of linoleic and linolenic acid in the lipids. The diet supplemented with 3.0% flaxseed oil showed the highest influence on the lipid composition of the broiler’s meat. [ABSTRACT FROM AUTHOR]

This is a study of the yields of stone fruits (apricots, cherries, peaches, nectarines and plums) on the territory of the Balkan countries for the period 2000-2016. A comparative assessment of the countries according to this indicator was made. Hierarchical cluster analysis and single factor analysis of variance were applied. For the period under study, the highest yield of apricots, cherries and plums is in Slovenia (157293.82 hg/ha, 313841.82 hg/ha and 1580446.53 hg/ha respectively). Greece (185991.47 hg/ha) and Italy (183474.12 hg/ha) have the highest yields of peaches and nectarines. The lowest yields of apricots are proven in Croatia (17966.59 hg/ha), followed by Bosnia and Herzegovina (21697.47 hg/ha). Bosnia and Herzegovina also has the lowest yields of cherries, peaches and nectarines (45717.29 hg/ha and 19491.18 hg/ha respectively). Slovenia has the highest proven instability of the yields of all crops. They are the most stable in Bosnia and Herzegovina. [ABSTRACT FROM AUTHOR]

A comparative mathematical analysis of economically important ampelographic indicators was performed in 32 local, introduced and newly bred white wine vine varieties. It was found that depending on the similarity and remoteness of the values of the studied indicators, the varieties are grouped into three generalized clusters. In the first, the varieties are characterized by a longer budding period and relatively lower productivity. In the second, they have similarities in the length of the budding period, long period of budding - technological maturity, moderate productivity, and close content of volatile acids in the wine. In the third, the newly bred two varieties Gergana and Misket Markovski, which are the most fertile and productive and with the smallest number of seeds in the berries. There is a high variability of the individual white wine varieties according to the studied economically valuable indicators. The indicators of bunch length and average weight per 100 berries have a stronger direct effect on the formation of the yield in individual varieties, and the average bunch weight, bunch width, percentage of mesocarp in berries, berry length and width, as well as the theoretical yield significantly affect indirectly the productivity of vines. [ABSTRACT FROM AUTHOR]

This study investigated the changes at the values of fertile eggs (%), hatchability of set eggs (%) and hatchability of fertile eggs (%) during the period 2009–2017 in five lines of hens. The changes of the values at these traits during different years were represented by mathematical models. Regarding the values of fertile eggs (%) in the studied years from 2009 to 2017 varied at diferent extent in the five hen genotypes. It was found that in the studied years 2009–2017 fertility of eggs (%) has the highest coefficient of determination in line STR (76%), and in hatchability of set eggs (%) – in line GN (75%). In the different years from 2009 to 2017, the hatchability of fertile eggs (%) was statistically closest values at the eggs of line E (80%). Third-order polynomial regression models depicted the values of these parameters of the different years in the best way. They represented wave-like patterns of parameters’ time course and instability in all lines of hens. [ABSTRACT FROM AUTHOR]

Agro-morphological traits of five Virginia tobacco hybrid combinations and standard Virginia 0514 were analyzed. The aim of the study was to group and evaluate hybrid combinations by stem height (SH), leaf number (LN), length of 12th leaf (LL), width of the 12th leaf (WL), days to 50% flowering (D50F), dry leaf yield. Hierarchical cluster analysis and analysis of the main components were applied. The grouping of hybrids in clusters found that Hybrid 27, Hybrid 33 and Hybrid 126 with a common parent component Virginia 385 have larger leave size and higher dry leaf yield, which determines not only their differentiation into a separate cluster, but also their strong distance from the other two hybrids and the Virginia 0514 standard. The Hybrid 126 has the longest growing season. The studied traits were transformed into two factors. The first includes length of 12th leaf and width of the 12th leaf, days to 50% flowering and dry leaf yield and explains 42.8% of the total variance. The second main component consists of plant height and leaf number, explains 32.5%. As a result of the study it was proved that the most effective would be the selection activity, aimed at the selection in the population of the second cluster on the grounds - length and width of the 12th leaf, dry leaf yield and days to 50% flowering. [ABSTRACT FROM AUTHOR]

The aim of the study is to evaluate the impact of morphological traits on the yield of Virginia tobacco lines with consolidated complex resistance to economically important viral diseases, Tobacco mosaic virus and Potato virus Y. The effect of the change in the height of the plant, the number of leaves, the sizes of the sixth and twelfth leaves on the yield is studied. Correlation analysis, regression analysis and Path analysis were applied. The direct and indirect influence of the studied traits on the yields is determined. The calculated correlation coefficients show a very strong, positive correlation between the yield and the length of the sixth leaf (0.985 **), the width of the sixth leaf (0.949 **), the number of leaves (0.934 **), the length (0.970 **) and the width of the twelfth leaf (0.966 **). In L 5, the length of the sixth leaf and the width of the twelfth leaf have a very strong direct effect on the yield. In L 6.3.3, the number of leaves and the length of the sixth leaf have the highest direct effect on the yield. [ABSTRACT FROM AUTHOR]

In an experiment with a greenhouse lettuce in the period 2018-2020, the influence of biological fertilization on the visual characteristics, taste indicators and nitrate content were studied. The biological fertilizers were tested: Arcobaleno, Italpolina, Lumbrical and the microbiological fertilizer Ecoprop NX with control of non-fertilized and mineral fertilization (MF) - NPK. The study was conducted with three varieties of salads: Maritima' - Batavia' type, Tuska' variety - Lolo rosa' type and Winter Butterhead' - Butterhead' type. An organoleptic assessment was performed on a five-point scale. A differentiated variety reaction was established. The Maritima' variety is the most responsive to the applied organic fertilizer. The variants with organic fertilization have a complex score from 3.52 for Ecoprop NX to 3.62 for Arcobaleno compared to 3.30 for the control of non-fertilized and 3.49 for the control of mineral fertilization. For the variety Tuska' only the variant fertilized with Italpolina exceeds the control and has the highest complex score of 3.82. Biological fertilization has improved the quality of the Winter ButterHead' variety and the complex assessment is from 3.14 in Italpolina to 3.41 in Lumbrical compared to the control variants non-fertilized 3.07 and MF 3.10. Fertilization with the tested biological fertilizers does not increase the amount of nitrates in lettuce leaves above the maximum permissible amounts set by the European Commission. [ABSTRACT FROM AUTHOR]

Fourteen varieties of peaches were included in the present study. The degree of blossom freezing (%) in two consecutive years 2019-2020 was studied. For this purpose, hierarchical cluster analysis and single-factor analysis of variance and Duncan's test were applied to assess the differences. It was found that the studied varieties can be grouped in four clusters according to similarity in the degree of frost in 2019 and in 2020. It was proved that in 2019 with the highest percentage of frost was 'El. 19-78' (98.33 %), followed by 'Ferlino', but with minor damage (50.67%). The varieties 'Evmolpia', 'Filina', 'Flavia', 'Redhaven' and 'El. 19-77' had no frozen blossoms. According to the degree of frost in 2020, the varieties formed three clusters, with 'Evmolpia' in a separate cluster, as a variety with minimal effects of low temperatures (59%). In 2020, the percentage of freezing of blossoms increased in most varieties: 'Ferlino' (92%), 'Puldin' (99%), 'Filina' (96%), 'Flavia' (92%), 'Maycrest' (98.67%), 'Redhaven' (99.67%), 'El. 7-59' (92%), 'El. 4- 22' (94.67%), 'El. 91-23' (96.23%), and 'El. 19-78' (93%). [ABSTRACT FROM AUTHOR]

The subject of this study is the following genotypes of cornel-tree: Pancharevski cylindrical, Atkov, Kazanlashki pearshaped, Vrachanski (Castel), Shandrian, Tsarigradski yellow, Yellow Hadzhiyski, Shumenski oblong and Yaltenski. They were grouped and assessed according to their genetic remoteness with respect to the pomological parameters: weight (g), length (mm) and width (mm) of the fruit as well as length of the stem (mm), weight (g), length (mm) and width (mm) of the stone. Hierarchical cluster analysis and factor analysis were applied for the processing of the experimental data. As a result of analyzes, the studied genotypes were found to be grouped into four clusters. The main indicators influencing the genotyping are: length of the fruit, length of the stem, weight and the length of the stone. The most distant genetically are Yaltenski and Shumenski oblong, on one side, and Pancharevski cylindrical and Atkov, on the other. [ABSTRACT FROM AUTHOR]

The present work studies the influence of the vegetation period in Virginia tobacco on the spread of the viruses PVYComplex (%), TMV (%), TSWV (%), CMV (%). To establish this relation, a correlation analysis was applied and the proven effects were represented by linear regression models. In 2014, with an increase of the period from replanting, the incidence of PVY-Complex (0.997**), TMV (0.860*) and TSWV (0.830*) increased significantly. The effect of the replanting on plant morbidity rate is similar (0.808**) also in 2015. In 2016, the very strong impact of the days from replanting on CMV (0.962**) and TSWV (0.907 **) viruses was proven. In 2017 the increase in the period from replanting leads to an increase in the percentage of diseased plants from PVY-Complex (0.946**), CMV (0.940**) and TSWV (0.976**). [ABSTRACT FROM AUTHOR]

The subject of study in the present work is the spread of TEV from the potvirus group in Virginia, Burley and Basmi tobacco varieties. The aim is to monitor the occurrence and development of TEV in these varieties grown in the central parts of southern Bulgaria and to analyze their resistance to this virus. During the period 2010 - 2019 immunological studies were carried out to prove the new viral tobacco disease in Bulgaria. A serological identification kit of the French company SEDIAG S.A.S. was used to demonstrate the virus. To establish TEV, a TAS-ELISA was performed at 1: 100 dilution of IgG. The virus was found to be sporadic. From the eight years of the study, TEV has been proven in four. The 2010-2011 period is characterized by a significant prevalence of TEV in Burley Group tobacco (14.3% and 12.7%, respectively). The virus is most strongly developed in 2019. It is evidenced in 60% of the tested samples from the Virginia variety. During the eight-year study period, only in 2010 TEV was found in isolates from the three tobacco varieties - Virginia, Burley and Basmi. As a result of the single-factor analysis of variance and Duncan's test, it was proven that tobacco from the Basmi variety was the most susceptible to infection with the TEV virus (0.165), followed by Virginia (0.136). Burley tobacco was found most resistant to the disease of TEV (0.126). [ABSTRACT FROM AUTHOR]

The present work studies the influence of plantation age and density on cornel-tree yields from a tree and per decar. The analyzed period ranges from five to eighty years, and the plantation density is between 45 and 159 trees per decare. The theoretical data are processed by a combination of mathematical approaches. A correlation analysis is applied to determine the extent and direction of the impact of age and density on the yield. The proven dependencies are represented by linear regression models. The number of trees has a significant, negative effect on the yield from a tree (R = - 0.678 **). The plantation age has a moderate, positive impact both on the yield from a tree (R = 0.397 **) and on the yield per decare (R = 0.436 **). As a result of the analyzes it was found that in case of shorter-term cultivation the plantation should consist of a larger number of trees, which at an earlier stage increase their productivity. However, if planning is longer, optimal yields will be achieved with fewer trees over a period of at least 20-25 years. [ABSTRACT FROM AUTHOR]